1. Field of the Invention
This invention relates to an improved, non-phosphate, non-bleach, agglomerated laundry booster which improves the performance of standard commercial laundry detergents in diverse wash liquor temperatures.
2. Description of Related Art
Bleaching compositions have long been used in households for the bleaching and cleaning of fabrics. Liquid and dry bleaches based upon hypochlorite chemical species have been used extensively, as they are inexpensive, highly effective, easy to produce, and stable. However, the advent of modem synthetic dyes and the use of modern automatic laundering machines have introduced new requirements in bleaching techniques, and have created a need for other types of bleaching compositions. In order to satisfy this need, peroxygen bleaches are sold which generate hydroperoxide ion, such as sodium perborate tetra- and monohydrate, as the oxidizing species. Alternatively, some manufacturers have experimented with so-called reducing bleaches, in which the "bleaching" agent is sodium thiosulfate. Despite the variety of laundry bleaches for use in various situations, certain consumers prefer to have yet further choices in improving the wash performance of laundry detergents and the resulting appearance of their washed fabrics.
France et al., U.S. Pat. No. 5,665,691, discloses a process for making a low density detergent composition by agglomerating a detergent surfactant paste and a dry starting material (builder) in which unpuffed borax pentahydrate, sodium carbonate and sodium phosphate are combined and then dried to a density of 300 g/L to about 450 g/L. France achieves fluffy particles by the essential step of drying its agglomerates in a drying apparatus with a minimum temperature of at least 50.degree. C. (122.degree. F.) and most preferably, as stated in its Example, at a temperature of about 200.degree. C. (392.degree. F.). Its process could be described as a method of puffing, or dehydrating, borax in situ. Moreover, besides the added energy required to produce the agglomerates of France et al., there is the added disadvantage of incorporating phosphates, which are less desirable now because of existing legislation in various regions to diminish or avoid their use in laundry and cleaning products.
Alkali metal tetraborate pentahydrate, also known as borax pentahydrate, has been used as a water soluble abrasive in co-pending and commonly assigned U.S. patent application Ser. No. 08/748,652, filed Nov. 14, 1996, of Blum et al., entitled "Powdered Abrasive Cleanser," and Ser. No. 08/718,059, filed Sep. 17, 1996, of Garner et al., entitled "Cleaner with Water Soluble Abrasive." However, both of these applications contemplate the use of borax pentahydrate as a water soluble abrasive in a hard surface cleaning and scouring application, and not as a builder in a fabric washing application, in which undissolved particulate matter, which may lead to residue on fabrics, is generally highly desirable to be avoided.